It’s no secret that pediatric food allergies are on the rise. In 2018, it was estimated that 1 in 13 children has at least one food allergy. Between 1997 and 2007, the prevalence in kids increased 18%, according to the Centers for Disease Control and Prevention.
Nobody knows the exact reason for the rise in food allergies. Some experts think this spike is due to increased awareness of food allergies, which has led to more children being tested. Another theory is lack of sunlight and vitamin D.
Yet another theory is improved hygiene – children today are not developing as many parasitic infections as in years past. Parasitic infections are normally fought by the same mechanisms involved in tackling allergies. With fewer parasites to fight, the immune system can turn against a patient's own body and cause allergic and autoimmune diseases.
Many parents don’t know that food allergies can also affect the gastrointestinal (GI) tract. Children’s Health is the only academic-affiliated pediatric food allergy center in North Texas, and we see many patients with food allergies that affect the GI system. In December, UT Southwestern will open a new medical center in Frisco, where the GI team will also treat children and food allergies.
GI food allergy symptoms can range from mild to debilitating. Treatment is available, and it all starts with identifying the food triggers that cause your child’s tummy troubles.
Common GI allergy symptom questions, plus answers
What foods are associated with allergies?
Six food groups cause approximately 90% of food-related allergic reactions: milk, wheat, egg, soy, fish/shellfish, and peanuts/tree nuts. Children often outgrow milk and egg allergies by the time they enter kindergarten. Fish, wheat, soy, and nut allergies are more likely to be lifelong and tend to cause more severe reactions.
What are common GI symptoms of food allergies?
Kids and adults with food-related allergies might experience:
- Irritation of the throat, stomach, or rectal area
- Stomach cramping
- Mucus or blood in the stools
Children with food allergies and GI symptoms often also have eczema, atopic dermatitis, asthma, or another of the many types of allergy conditions.
How are food allergies diagnosed?
Families typically discover food allergies through trigger symptoms. For example, I am allergic to almonds, and when I accidentally eat something with almond in it, my lips begin to tingle and my throat starts to close. For GI symptoms, parents might notice their child develops stomach pain, vomiting, or diarrhea within hours of eating triggering food.
Children can have skin testing (such as skin prick or patch testing) to find out whether they are sensitive or allergic to a particular type of food. These kids often can manage symptoms by avoiding trigger foods or swapping them for specially prepared alternatives. Families today have more allergy-friendly food options than ever thanks to brands and restaurants that offer gluten-free, soy-free, and vegan (egg- and milk-free) items on their menus.
However, sometimes no particular food group is identified as a trigger for a child’s reactions, even after trying an elimination diet. In these cases, the condition might not be a food allergy at all, but something more complex and rare.
When food-related symptoms aren’t allergies
Children with gastrointestinal symptoms in presence of other atopic diseases, such as eczema, atopic dermatitis, or asthma should be tested for eosinophilic gastrointestinal diseases (EGIDs). These inflammatory GI conditions affect fewer than 20 out of 100,000 patients in the U.S.
EGIDs are often diagnosed in children and involve an influx of eosinophils — a type of white blood cells that fight allergens — in the GI tract and the bloodstream, causing symptoms, including:
- Abdominal pain
- Blood in the stools
- Feeding issues (in infants)
- Oral aversion (fear or reluctance to eat, drink, or breastfeed)
- Trouble swallowing
Left untreated, EGIDs can cause malnutrition, iron-deficiency anemia, and damage to the GI tract.
We diagnose EGIDs by first taking a thorough history of the patient’s symptoms including food allergies and aversions, as well as reviewing any allergy testing that has been done. Patients with a personal or family history food/environmental allergy conditions such as eczema or asthma might be at increased risk to develop EGIDs.
Sometimes no particular food group is identified as a trigger for a child’s reactions, even after trying an elimination diet. In these cases, the condition might not be a food allergy at all, but something more rare.
Blood tests, especially eosinophil counts, may not be considered a good marker in diagnosing EGID. Depending on the duration and severity of symptoms and signs, and in patients we highly suspect might have EGID, we can schedule an endoscopy to obtain tissue to examine for the presence of eosinophils and associated inflammation.
These conditions typically are chronic and recurring. Depending upon the location of the disease in the GI tract, medication including proton pump inhibitors or steroids can be used. Before trying steroids, patients who are interested in the dietary therapy are advised to try an elimination diet in which patients avoid the six food groups that cause 90% of food-related allergic reactions: milk, wheat, egg, soy, fish/shellfish, and peanuts/tree nuts.
Ongoing research related to food allergies
Christopher Parrish, M.D., and I manage the Dallas Eosinophilic Esophagitis Program (DEEP) at Children’s Health along with Edaire Cheng, M.D., who is the research director of the DEEP clinic.
Dr Cheng is creating a bio-depository in which she collects blood samples and tissue specimens to develop new drugs and identify novel therapeutic targets to treat EGIDs. We are also participating in a clinical trial to study the effect of new drug dupilumab on patients with eosinophilic esophagitis.
As food allergies continue to rise, parents and providers need to work closely together to protect the gastrointestinal health of pediatric patients. Together, we can help kids manage their condition and reduce the risk of long-term complications.